Advance Publications’ Newhouse Newspapers is breaking its vow to avoid layoffs at its non-unionized newspapers.

The company, which locally owns the Star-Ledger in Newark and the Staten Island Advance, yesterday told employees at its 20 newspapers about the change, which will go into effect next February.

“It’s a transformational time in the industry,” said Steven Newhouse, president of AdvanceNet the company’s Internet operations.

“The situation is so challenging, we felt the pledge in many respects became a deterrent to actions that could actually save the daily papers and jobs for the majority of employees. We needed to have the flexibility to reduce staffs in order to keep daily newspapers as dailies.”

The company last year gave more than 200 early retirement packages to employees in newsrooms at the Star-Ledger and the smaller Trenton Times after first threatening to close the papers if enough people didn’t accept early retirement.

But even before announcing yesterday that it was rescinding the no-layoff policy, the company has slashed jobs where it can.

Its Ann Arbor, Mich., paper laid off about 90 people when it switched to an online edition with printed versions twice a week.